Plate shaving machine



727 F STEDT W. J. LOFSTEDT PLATE SHAVING MACHINE May 14, 1940.

4 Sheet-Sheet 1 Filed Oct. 4, 1958 aux //\/A/E/\/ WILLIAM J. LO En 7 fTURNE May 14, 1940.

W. J. LOFSTEDT PLATE SHAVING MACHINE Filed Oct. 4, 1938 Lilli 1X1" 4 Sheets-Sheet 5 v Z/EN TLZR WlLLlAM J. LOFSTEDT 9! Y L 7, v u v u \1 v \J v \T y 14, 1940- w. J. LOFSTEDT 2.200.628

PLATE SHAVING MACHINE Filed Oct. 4, 1938 4 Sheets-Sheet 4 NV/E/VTUR wuLuAm J. LOFSTEDT 7 7 TERA/E draulic means for operating the slide 26 without requiring excess movement on the part of the actuator.

Mounted on the bed I? is a cutter housing GI within which journal the roughing cutter shaft 62, the finishing cutter shaft 63 and the brush shaft 64. Mounted on the roughing cutter shaft 62 is a roughing cutter 65 having spiral cutting edges 66, the shape of which will be seen in Fig. 6.

Rotation is supplied to the shaft 62 by means of the chain 6! which passes around the sprocket wheels 68 and 69. The sprocket wheels 59 are secured on the shaft 62. The sprocket wheels 68 are secured on the shaft it! which is supported by the standards '5! on the threaded post 72 which is held in position by the nuts "F3. On the shaft 1!] are also mounted the sprocket wheels '14 whose chain 75 passes around the sprocket wheels 76 on the finishing cutter shaft On the shaft 63 is mounted a finishing cutter i? whose cutting edges I8 are concentric with the shaft 53. The form of the finishing cutter tooth is shown in Fig. 7.

On the shaft 2'0 are mounted the multiple drive sheaves 79 and 80. The sheaves l9 carry the V-belts 8i which pass around the sheaves 82 on the shaft 83 of the motor 84. The sheaves 86 are provided with a belt 85 which passes around the sheave 86- by means of which the pump 8'! is driven. The pump 8'. is provided with an intake pipe 83 which communicates with a reservoir 89. A discharge pipe 99 is used to convey the lubricant to the spray pipes Si.

Between the cutters i5 and TI is disposed a housing 32 for the hold-down rollers 93 whose shafts 94 are supported in the vertically slidable members 95 whose upper ends 96 are disposed within the openings 9'! formed within the housing 62. The yoke S8 is disposed between the members 95 and has its ends 99 projecting into the slots M8 which are formed within the memhers 95. The yoke 98 is provided with an upturned shank I0! which is slidable within the opening 522 in the housing 92.

Mounted in the shank lot is a sleeve I93. A spring 494 serves to urge the members I03 and 98 apart. The upper end of the member I83 bears against the eccentric shaft I85 whose position is determined by means of the hand lever Hi6 and fixed by means of the bolt If)? which occupies an arcuate slot It!!! in the lever Hi6. It can be seen in Fig. 8 that there are a plurality of rollers 93 and a plurality of eccentrics I05 by means of which the pressure on the rollers 93 may be varied at will.

It is noted that the housing 82 has its side I09 curved to conform with the finishing cutter I! and that this curvature extends well up to the point H8 which is just below the brush III. The brush I i I is mounted on the shaft 64, which has secured thereon a gear H2 which meshes with the idler pinion US which in turn meshes with the gear 5 Hi on the finishing cutter shaft 63.

On the roughing cutter shaft 62 is mounted a spiral gear H5 which meshes with a spiral pinion H5 which is secured on the shaft Ill. On the shaft H! is secured a gear I I8 which meshes with the gear H9 on the shaft I29 which carries the conveyor drive sprockets I2I whose chains 22 carry the flights I23.

Over the finishing cutter TI is placed the inclined hood i2 1 having a slot I25 formed horizon tally through same. In the slot I25 is disposed the grinding wheel E26 by means of which the finishing cutter may be maintained in the desired condition. A motor I2! is mounted on the plate I 28 which is slidable along the slot I25. A roller I29 of felt or other suitable material is mounted on the outer side of the finishing cutter 17.

There is also provided a chip box I30 which is mounted on the casters I3I.

It will be noted that the roughing cutter shaft 52 is supported on the vertically movable slide I32 which is mounted in the cutter housing 6|. The slide I32 is provided with an inclined face I 33 which is separated from the housing (H by the wedge I34 having an outwardly extending lug I35 through which extends the bolt I36 by means of which the lateral position of the wedge I3 1 may be varied and consequently the vertical position of the roughing cutter 65 may be varied.

It is desirable to provide a plate I3! which extends from the underside of the roughing cutter 65 along the underside of the conveyor chains I22. There is illustrated a printing plate I38 which may be of any of the kinds used in the printing art.

The operation of the machine is as follows:

Assuming that the printing plate I38 is to be shaved to a predetermined thickness, it is placed face down upon the table 23 which by means of the hand wheel 28 is moved to provide the required clearance under the finishing cutter IT. The roughing cutter 85 is then adjusted by means of the bolt I36 to bring the thickness of the plate to a dimension which can be handled by the finishing cutter I1.

It will be noted that the roughing cutter 65 is driven at a higher speed than is the finishing cutter '5'. and that the roughing cutter G 5 has its cutting edges formed at a smaller spiral than are the cutting edges of the finishing cutter I7. It will also be noted that the work engaging face of the finishing cutter I! is concentric with its axis providing thereby a combined cutting and burnishing and holding down action which results in a perfectly smooth and uniformly finished surface on the back of the printing plate I38 when the work is completed. The plate I38 having been placed upon the table 23 is placed in the corner to which it would naturally be moved by the cutting action. As the button 5'! is depressed, it causes the slide 20 to move to the left as viewed in Fig. 1 and causes the plate I38 to move first beneath the cutter 65 where the major portion of its exterior metal is removed and thence to pass under the hold-down rollers 93 and thence under the finishing cutter T! where the shaving operation is completed.

It will be observed that as the work progresses. the larger chips are thrown by the roughing cutter 65 toward the conveyor chains I 22 and that the brush i I I will remove from the finishing cutter 'F'I' the particles which adhere thereto and tl-irowthem upon the roughing cutter 65 from whence they are delivered to the conveyor chain I22.

In most cases it is desirable to keep a supply of lubricant playing upon the cutters 65 and IT. Should the finishing cutter 'I'I become dull it is only necessary to place the grinding wheel I26 in position and slide it longitudinally as the cutter TI is revolved.

The function of the roller I29 is merely to hold the plate I38 down as it leaves the finishing cutter 11.

It must be understood that while I have illustrated certain details of construction in connection with this invention that the exact nature thereof is of little importance. For example, the-re may be employed any type of drive mechanism for the cutters or for operating the. table 23, or any suitable type of control valve mechanism for the hydraulic actuator may be used Without departing from the spirit of this inven tion.

I claim:

1. A plate shaving machine having in combination a vertically adjustable table having side and end stops thereon, means for moving said table horizontally, a finishing cutter disposed above said table, a roughing cutter adjustably disposed above said table and means for varying the relative vertical positions of said cutters.

2. A plate shaving machine described in claim 1 together with a grinding wheel associated with said finishing cutter and having means for slidably moving said wheel in parallelism with the axis of the finishing cutter.

3. The plate shaving machine described in claim 1 together with a revolvable brush adapted to engage the cutting face of said finishing cutter and sweep materials therefrom toward said roughing cutter.

4. The plate shaving machine described in claim 1 together with a plurality of spring urged rollers adapted tobear upon a plate as said plate passes between said cutters.

5. A plate shaving machine as described in claim 1. together with a conveyor disposed along the discharge side of said roughing cutter adapted to move chips laterally therefrom.

6. A plate shaving machine having in combination a pedestal, a horizontal bed disposed on said pedestal, a vertically adjustable and horizontally movable table mounted on said bed, said table having side and end stops thereon, a horizontal finishing cutter mounted across said table, a revolvable brush associated with said finishing cutter, a roughing cutter adjustably mounted with relation to said finishing cutter and a plurality of hold-down rollers disposed between said cutters, said cutters being characterized by having the edges of both cutters spirally formed and by having the cutting face of the finishing cutter concentric with the axis thereof and set at a d lesser spiral angle than are the cutting edges of the roughened cutters.

'7. The plate shaving machine described in claim 6, together with means for supplying lubricant to the cutter thereof.

WILLIAM J. LOFSTEDT. 

